A Novel Cadmium(Ⅱ) Complex Based on Asymmetric Dicarboxylate and N-Auxiliary Ligand: Synthesis, Crystal Structure and Properties

One Cd（II） complex based on dicarboxylate and N-auxiliary ligand, namely, [Cd（aip）（m-bix）]n （1, H2aip = 5-aminoisophthalic acid, m-bix = 1,3-bis（imidazol-l-yl-methyl）ben- zene）, was successfully synthesized under hydrothermal conditions. Single-crystal X-ray diffraction analysis reveals that 1 belongs to the orthorhombic system, space group Pbca with a = 14.0790（11）, b = 17.0038（15）, c = 17.3191（16）, V= 4146.1（6） A3, Z = 8, D,. = 1.698 g.cm＂3, p = 1.095 mm-1, F（000） = 2128, the final R = 0.0268 and wR = 0.0623. Complex 1 is a three-dimensional architecture with fsc-3,5-Cmce-1 topology, in which the metal ions act as rare 5-connected nodes. The TGA, XRD and luminescent properties of I were studied.

Studies on Epitaxial Polymerization of 1,3-Bis(3-quinolyl)-1,4-butadiyne

During investigating what causes the low yield of the polymerization product of 1,4-bis(quinolyl)-1,3-butadiyne(DQ), we found that the DQ crystals formed on the surface of PDQ cauld be polymerized to give blue crystals, in which DQ could be sublimated and crystallized on the surface of PDQ film. According to the experimental results, the reason why the DQ crystals can be polymerized is that the sublimation of DQ changes the molecular orientation of DQ in the crystal. The crystals formed in epitaxial growth on the surface of DQ or PDQ during sublimation of DQ are suitable for 1,4-addition polymerization.

A Novel Neodymium-tartrate Complex with Distinctive Rare Topology:Hydrothermal Synthesis and Crystal Structure

One novel neodymium-tartrate complex exhibiting distinctive rare topology,name-ly,[Nd（TTA）1.5（H2O）]·H2O（1,H2TTA = tartaric acid）,was successfully synthesized by the reaction of neodymium-oxide with H2TTA under hydrothermal conditions.Single-crystal X-ray diffraction analysis reveals that 1 belongs to the monoclinic system,space group P21/c with a = 6.0357（13）,b = 7.6106（17）,c = 24.389（5） ,β = 100.136（5）°,V = 1102.8（4） 3,Z = 4,Dc = 2.423 g·cm-3,μ = 4.763 mm-1,F（000） = 776,the final R = 0.0689 and wR = 0.2191.In complex 1,the 2D layer consisting of μ4-ligands and 4-connected Nd（III） centers is a rare example of uni-nodal net of（42.64） topology.The 2D layers are further connected by μ2-TTA2-ligands to give a 3D（42.64）（42.67.8） topological structure,where the Nd（III） atoms act as rare 5-connected topological blocks.

Surface Topological Glycosylation-Mediated Mucoadhesion of Bacteria

Sugar moieties present on bacterial surface serve as pivotal regulators of bacterial activity.Precisely adjusting the abundance and distribution of surface sugar moieties can offer an important approach to manipulating bacterial behavior,but has been proven to be difficult.Herein,surface topological glycosylation is reported to mediate the interaction of bacteria with mucous layer.Alkynes functionalized by sugar moieties with different branching are synthesized through iterative Michael addition and amide condensation reactions.By a copper-catalyzed azide-alkyne cycloaddition,the resulting compounds with different branching structures can be attached onto bacterial surface that is modified with azido groups.As a proof-of-concept study,a set of topologically glycosylated probiotics(TGPs)is prepared using linear,two-branched,and tetra-branched compounds,respectively.The interaction between mucin and TGPs was studied and the results demonstrate that,compared to unmodified bacteria,TGPs exhibit an enhanced adhesive capacity to mucin,which increases with the branching numbers.Similar binding trend is observed in ex vivo colonic mucus adhesion experiments and bacteria glycosylated with tetra-branched compounds display the highest binding efficiency.This work proposes a chemical method to tune the abundance and distribution of sugar moieties on bacteria,providing unique significant insights into the manipulation of bacterial behavior through surface modification.

Pressure-Induced Topochemical Polymerization toward Advanced Energetic Materials

Pressure produces closely packed,high-density materials,thereby providing a promising strategy to obtain high-energy-density materials.However,new phases or structures of energetic materials at high pressure are often not quenchable under ambient conditions.In this work,high-pressure topochemical methodology is first introduced for the preparation of stable energetic materials under ambient conditions.A pressure-induced polymerizable energetic material named PIP-1 is designed and prepared.The experimental measurements demonstrate that the polymerization of PIP-1 is caused by the breakage of C≡C bonds and the generation of C=C bonds.In accord with the experimental results,density functional theory calculations further revealed that the monomer PIP-1 is polymerized to generate 1D PIP-1 tape,and the density of polymerized PIP-1 is increased by 4.9%upon decompression.The successful realization of high-energy-density structure using high pressure showcases a new design strategy for advanced polymerizable energetic materials.

Phase-mediated controllable intramolecular and intermolecular photocycloadditions assisted by supramolecular templates

Understanding and controlling supramolecular template effect assembly via a photochemical reaction in different solid and solution phases is one of the main topics in photochemistry. Here, an interesting case of phase-mediated controllable intramolecular/intermolecular photochemical [2+2] cycloadditions assisted by supramolecular templates was demonstrated. Direct irradiation of the complexes in solution yields intramolecular photoproducts exclusively, whereas exposure of the solid powder sample under the same conditions yields intermolecular dinuclear species quantitatively. The nature of the phase and supramolecular interaction affects the geometrical arrangements of the metallacycles, leading to different cycloaddition products under photoirradiation. The crystal structures of different products were investigated by single-crystal X-ray diffraction, nuclear magnetic resonance(NMR) spectrometry, and electrospray ionization mass spectrometry(ESI-MS).

Maleimide Chemistry:Enabling the Precision Polymer Synthesis

Herein is presented a compilation of the main characteristics of maleimide chemistry in developing the precisely controlled polymers,including the design of sequence-controlled polymers,topological polymers,and polymeric single-chain nanoparticles.The synthetic methods,relied on the versatilities of the maleimide moieties as a latent monomer which leads to an efficient alternative in various innovative applications,especially in self-healing material,self-reporting materials for real-time monitoring,and also in data storage and anticounterfeiting technologies.The core of the content in this review is focused on the up-to-data advances and publications on the major of maleimide chemistry in our research group.

Spectroscopic/Microscopic Elucid

The Arundo donax is a typical fast-growing species from the family Gramineae,which is widely cultivated in China.With a huge yield of A.donax in China,this plant offers great potential for biofuels production.The different types of organization of cell and the tissue in the A.donax could influence the efficiency of enzymatic hydrolysis.In this study,A.donax was subjected to 0.5%(w/w)sulfuric acid(H2SO4)for pretreatment at 140℃for 10 min,20 min,40 min,and 60 min,respectively.The changes in microstructure,chemical composition,topochemical properties were comprehensively analyzed.Using a series of spectroscopic and microscopic techniques including Fourier transform infrared spectroscopy(FT-IR),X-Ray diffraction(XRD),polarized light microscopy(PLM),and confocal Raman microscopy(CRM)to obtain the correlative structural and chemical information.Analysis results of chemical composition,FT-IR spectra and XRD indicated that with increasing reaction time,more hemicellulose and lignin would be removed.Correspondingly,there was an obvious increase of the cellulose relative crystallinity via extending reaction time.Results of the PLM observations showed that the birefringence gradually dimmed due to the diminishing of the cellulose component.Furthermore,the CRM mapping images showed the lignin component in compound middle lamellar(CML)was difficult to remove relatively as compared with that in secondary walls.These results indicated that the combination of spectroscopic and microscopic elucidation could give an insightful understanding of chemical changes in cellular level during pretreatment.